Introduction to NFS configuration of Debian and UbuntuLinux

Article Title: Introduction to NFS configuration of Debian and UbuntuLinux. Linux is a technology channel of the IT lab in China. Including desktop applications, Linux System management, kernel research, embedded systems, open source, and other basic classification NFS (Network File System) you can share directories of different hosts (different OS) over the network-you can mount directories of remote hosts through NFS to access these directories, just like accessing local directories!
　
Generally, nfs can be used to easily share unix-like systems. However, if you want to share a file between unix-like and windows systems, you have to use samba!
　
NFS runs on the basis of SUN's Remote Procedure Call (Remote Procedure Call). RPC defines a system-independent method for inter-process communication. Therefore, the NFS server can also be viewed as an RPC server.
　
Because NFS is an RPC service program, you must map the port before using it-set through portmap. For example, when an NFS client initiates an NFS service request, it must first obtain a port ). Therefore, it first obtains port number through portmap. (not only NFS, but portmap needs to be set before all RPC service programs are started)
　
Before starting the RPC service (such as NFS), you need to start the portmap service! (For more information about whether nfs and portmap exist in the current system, see the "NFS installation" section.
　
Several NFS-related files and commands
　
1./etc/exports
　
The access to the NFS volume is approved by exports, which enumerate several hostnames that have the right to access the file system on the NFS server.
　
2./sbin/exportfs
　
Maintain NFS resource sharing. You can use it to reset the/etc/exports shared directory, uninstall the NFS Server shared directory, or share it again.
　
3./usr/sbin/showmount
　
It is used on NFS Server, while showmount is mainly used on Client. Can I use showmount? Zookeeper NFS shared directory resources.
　
4./var/lib/nfs/xtab
　
NFS record document: You can view which clients are connected to the NFS host.
　
The following are not directly responsible for NFS. In fact, they are responsible for all RPC
　
5./etc/default/portmap
　
In fact, portmap maps all the RPC service ports. Its content is very simple (detailed later)
　
6./etc/hosts. deny
　
Set the host to reject the portmap service
　
7./etc/hosts. allow
　
Set the host that allows the portmap service
　
Install NFS
　
By default, the NFS server is not installed on Debian/Ubuntu. First, install the NFS service program:
　
$ Sudo apt-get install nfs-kernel-server
　
(When nfs-kernel-server is installed, apt will automatically install nfs-common and portmap)
　
In this way, the host is equivalent to the NFS Server.
　
Similarly, if the target system is an NFS client, you must install the NFS client program. For Debian/Ubuntu systems, you need to install nfs-common.
　
$ Sudo apt-get install nfs-commmon
　
Both nfs-common and nfs-kernel-server depend on portmap!
　
Configure NFS
　
NFS is an RPC server program. Portmap is used to map the port numbers of your RPC. Configure portmap first.
　
Configure portmap
　
Method 1: edit/etc/default/portmap and remove-I 127.0.0.1.
　
Method 2: $ sudo dpkg-reconfigure portmap, shocould portmap be bound to the loopback address? Select N.
　
Configure/etc/hosts. deny
　
(Prohibit any host (host) from connecting to your NFS server), add:
　
### NFS DAEMONS
　
Portmap: ALL
　
Lockd: ALL
　
Mountd: ALL
　
Rquotad: ALL
　
Statd: ALL
　
Configure/etc/hosts. allow
　
Allow hosts you want to establish connections with your NFS server. The following steps allow any host whose IP address starts with 192.168.2 (connected to the NFS server), or specify a specific IP address. See hosts_access (5) and hosts_options (5) on the man page ). Join:
　
### NFS DAEMONS
　
Portmap: 192.168.2.
　
Lockd: 192.168.2.
　
Rquotad: 192.168.2.
　
Mountd: 192.168.2.
　
Statd: 192.168.2.
　
/Etc/hosts. deny and/etc/hosts. allow set access to portmap. Using these two configuration files is a bit similar to "mask. Currently, all users are prohibited from accessing portmap in/etc/hosts. deny. Then, some users can access portmap in/etc/hosts. allow.
　
Run $ sudo/etc/init. d/portmap restart to restart portmap daemon.
　
Configure/etc/exports
　
The NFS mount directory and permissions are defined by the/etc/exports file.
　
For example, to share the IP address of 192.168.2. * In the/home/zp/share directory of my home directory, add the following statement at the end of the file:
　
/Home/zp/share 192.168.2. * (rw, sync, no_root_squash)
　
Or:/home/zp/share 192.168.2.0/24 (rw, sync, no_root_squash)
　
192.168.2. * The NFS client in the network segment can share the contents of the NFS server/home/zp/share directory. The user has the read and write permissions, and the user's identity after entering the/home/zp/share directory is root
　
It is best to add sync. Otherwise, a warning will be given when $ sudo exportfs-r is used. sync is the default option of NFS.
　
Run $ showmount-e to view the NFS server's export list.
　
If/etc/exports is changed, run $ sudo exportfs-r update.
　
Run $ sudo/etc/init. d/nfs-kernel-server restart to restart the nfs service.
　
/Etc/exports is actually the core configuration file of the nfs server. Laruence's Linux private dish lists the writing methods of some exports files.
　
Test NFS
　
Try mounting the local disk (assuming the IP address of the local host is 192.128.2.1, Mount/home/zp/share to/mnt)
　
$ Sudo mount 192.168.2.1:/home/zp/share/mnt
　
Run $ df to check the result
　
$ Sudo umount/mnt
　
Note the read/write permissions of the copied file!
　
In addition, some parameters can be used:
　
Add parameters: mount-o nolock, rsize = 1024, wsize = 1024, timeo = 15 192.168.2.130:/tmp // tmp/